Tens of thousands of middle class children could be officially classed as poor
because of planned cuts to child benefit, The Daily Telegraph can disclose.

Research has found that 8,000 middle class families, most with three children or more, will be pushed below the poverty line by the cuts. In all 20,000 children would be effected.

This is because their disposable income after the costs of meeting monthly mortgage payments will be so small that they will be officially seen as poor.

From January 2013, anyone living in a household where someone earns more than £42,475 will be barred from receiving child benefit. Campaigners have said that a typical family with two children will be £1,700 worse off as a result.

Howard Reed, of Landman Economics, calculated the estimates by examining the effect on those just above the threshold.

Child Poverty Action Group looked at a number of different scenarios to work out the effect of the cut which is due to come into force in January next year.

Official estimates suggest that the ‘after housing costs’ poverty line is up to £84 per week of disposable income for every family member in 2012/13.

However cases cited by CPAG show how easily a middle class family on a good wage can be pushed into technical poverty by the changes.

It found that some families with mortgages could be left with less than £70 a week per family member to live in, after mortgage costs had been paid from next income.

Alison Garnham, CPAG’s chief executive, said the plans, which will be put to a vote of MPs later this summer, “will cause significant hardship for thousands of families”.

He said: “Ministers are well aware of the high housing costs people face and should have taken more account of it before rushing out a policy that had not been properly thought through.

“On typical mortgages some families will be left with less than £10 a day per family member for all their food, clothes, transport, energy bills and other outgoings, which is comparable to families currently below the poverty line.

“Families will be hurting and the government must start listening. We are completely behind the public on the view that higher earners should be making a fair contribution to deficit reduction, but the child benefit cap policy is fundamentally flawed.

“It should be scrapped altogether in favour of an approach that has no cliff edges and that ensures all higher earners contribute, rather than targeting the whole burden only on those with children.”

CPAG found that a family with three children and a single earner on £43,000 with a £197,000 mortgage over 25 years would be on the poverty line. This is because they would have just £68.04 a week in disposable income for each family member after their mortgage payments.

In contrast, a couple with four children - CPAG calculated - would only be able to afford an interest mortgage of £150,000 on payments of £459 a month before they were pushed below the poverty line.

In contrast, a couple with four children - CPAG calculated - with a single earner on £43,000 would only be able to afford a 5 per cent interest only mortgage of £130,000 on payments before they were pushed below the poverty line.